Stanford Thesis Defense Explores Cryogenic Charge Sensing for Sub-MeV Dark Matter Searches
Jadyn Anczarski, a Ph.D. Candidate at KIPAC, Stanford University, presented a thesis defense on 'Cryogenic Charge Sensing for Dark Matter Searches: Quantum Sensing and Narrow-Gap Materials.' The research addresses the challenge of detecting sub-MeV dark matter, a mass range largely unexplored due to the limitations of current semiconductor detectors, which have eV-scale bandgaps. The SPLENDOR Collaboration, where Anczarski conducts research, aims to synthesize novel narrow-gap semiconductors with bandgaps in the order of 10–100 meV. Detecting ionization in these materials requires a new detector platform capable of easily swapping candidate substrates without complex fabrication, while achieving sub-electron charge resolution. The thesis details the development of SPLENDOR’s first charge amplifier, a two-stage design based on low-noise cryogenic transistors (CryoHEMTs), which achieved a charge resolution of approximately 20 electrons, with a projected resolution of about 3 electrons. Additionally, it prese...